From patchwork Thu Jan 8 00:26:52 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 426428 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id AC4441400DD for ; Thu, 8 Jan 2015 11:04:36 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753708AbbAHAEf (ORCPT ); Wed, 7 Jan 2015 19:04:35 -0500 Received: from v094114.home.net.pl ([79.96.170.134]:54684 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753386AbbAHAEe (ORCPT ); Wed, 7 Jan 2015 19:04:34 -0500 Received: from afec205.neoplus.adsl.tpnet.pl (95.49.106.205) (HELO vostro.rjw.lan) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer v0.80) id 233fd30a869f870a; Thu, 8 Jan 2015 01:04:31 +0100 From: "Rafael J. Wysocki" To: Linux PCI Cc: Linux Kernel Mailing List , Linux PM list , Bjorn Helgaas , Alan Stern , Aaron Lu , Mika Westerberg Subject: [RFC][PATCH] PCI / PM: Avoid resuming PCI devices during system suspend Date: Thu, 08 Jan 2015 01:26:52 +0100 Message-ID: <1460212.bInrzeZle0@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/3.16.0-rc5+; KDE/4.11.5; x86_64; ; ) MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Rafael J. Wysocki Commit f25c0ae2b4c4 (ACPI / PM: Avoid resuming devices in ACPI PM domain during system suspend) modified the ACPI PM domain's system suspend callbacks to allow devices attached to it to be left in the runtime-suspended state during system suspend so as to optimize the suspend process. This was based on the general mechanism introduced by commit aae4518b3124 (PM / sleep: Mechanism to avoid resuming runtime-suspended devices unnecessarily). Extend that approach to PCI devices by modifying the PCI bus type's ->prepare callback to return 1 for devices that are runtime-suspended when it is being executed and that are in a suitable power state and need not be resumed going forward. Signed-off-by: Rafael J. Wysocki --- drivers/pci/pci-acpi.c | 17 +++++++++++++++++ drivers/pci/pci-driver.c | 11 ++++++----- drivers/pci/pci.c | 21 +++++++++++++++++++++ drivers/pci/pci.h | 6 ++++++ 4 files changed, 50 insertions(+), 5 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Index: linux-pm/drivers/pci/pci.c =================================================================== --- linux-pm.orig/drivers/pci/pci.c +++ linux-pm/drivers/pci/pci.c @@ -521,6 +521,11 @@ static inline int platform_pci_run_wake( pci_platform_pm->run_wake(dev, enable) : -ENODEV; } +static inline bool platform_pci_need_resume(struct pci_dev *dev) +{ + return pci_platform_pm ? pci_platform_pm->need_resume(dev) : false; +} + /** * pci_raw_set_power_state - Use PCI PM registers to set the power state of * given PCI device @@ -1999,6 +2004,22 @@ bool pci_dev_run_wake(struct pci_dev *de } EXPORT_SYMBOL_GPL(pci_dev_run_wake); +/** + * pci_dev_keep_suspended - Check if the device can stay in the suspended state. + * @dev: Device to check. + * + * Return 'true' if the device is runtime-suspended, it doesn't have to be + * reconfigured for system wakeup and the current power state of it is + * suitable for the upcoming (system) transition. + */ +bool pci_dev_keep_suspended(struct pci_dev *dev) +{ + if (!pm_runtime_suspended(&dev->dev) || platform_pci_need_resume(dev)) + return false; + + return pci_target_state(dev) == dev->current_state; +} + void pci_config_pm_runtime_get(struct pci_dev *pdev) { struct device *dev = &pdev->dev; Index: linux-pm/drivers/pci/pci.h =================================================================== --- linux-pm.orig/drivers/pci/pci.h +++ linux-pm/drivers/pci/pci.h @@ -50,6 +50,10 @@ int pci_probe_reset_function(struct pci_ * for given device (the device's wake-up capability has to be * enabled by @sleep_wake for this feature to work) * + * @need_resume: returns 'true' if the given device (which is currently + * suspended) needs to be resumed to be configured for system + * wakeup. + * * If given platform is generally capable of power managing PCI devices, all of * these callbacks are mandatory. */ @@ -59,6 +63,7 @@ struct pci_platform_pm_ops { pci_power_t (*choose_state)(struct pci_dev *dev); int (*sleep_wake)(struct pci_dev *dev, bool enable); int (*run_wake)(struct pci_dev *dev, bool enable); + bool (*need_resume)(struct pci_dev *dev); }; int pci_set_platform_pm(struct pci_platform_pm_ops *ops); @@ -67,6 +72,7 @@ void pci_power_up(struct pci_dev *dev); void pci_disable_enabled_device(struct pci_dev *dev); int pci_finish_runtime_suspend(struct pci_dev *dev); int __pci_pme_wakeup(struct pci_dev *dev, void *ign); +bool pci_dev_keep_suspended(struct pci_dev *dev); void pci_config_pm_runtime_get(struct pci_dev *dev); void pci_config_pm_runtime_put(struct pci_dev *dev); void pci_pm_init(struct pci_dev *dev); Index: linux-pm/drivers/pci/pci-acpi.c =================================================================== --- linux-pm.orig/drivers/pci/pci-acpi.c +++ linux-pm/drivers/pci/pci-acpi.c @@ -501,12 +501,29 @@ static int acpi_pci_run_wake(struct pci_ return 0; } +static bool acpi_pci_need_resume(struct pci_dev *dev) +{ + struct acpi_device *adev = ACPI_COMPANION(&dev->dev); + + if (!adev || !acpi_device_power_manageable(adev)) + return false; + + if (device_may_wakeup(&dev->dev) != !!adev->wakeup.prepare_count) + return true; + + if (acpi_target_system_state() == ACPI_STATE_S0) + return false; + + return !!adev->power.flags.dsw_present; +} + static struct pci_platform_pm_ops acpi_pci_platform_pm = { .is_manageable = acpi_pci_power_manageable, .set_state = acpi_pci_set_power_state, .choose_state = acpi_pci_choose_state, .sleep_wake = acpi_pci_sleep_wake, .run_wake = acpi_pci_run_wake, + .need_resume = acpi_pci_need_resume, }; void acpi_pci_add_bus(struct pci_bus *bus) Index: linux-pm/drivers/pci/pci-driver.c =================================================================== --- linux-pm.orig/drivers/pci/pci-driver.c +++ linux-pm/drivers/pci/pci-driver.c @@ -653,7 +653,6 @@ static bool pci_has_legacy_pm_support(st static int pci_pm_prepare(struct device *dev) { struct device_driver *drv = dev->driver; - int error = 0; /* * Devices having power.ignore_children set may still be necessary for @@ -662,10 +661,12 @@ static int pci_pm_prepare(struct device if (dev->power.ignore_children) pm_runtime_resume(dev); - if (drv && drv->pm && drv->pm->prepare) - error = drv->pm->prepare(dev); - - return error; + if (drv && drv->pm && drv->pm->prepare) { + int error = drv->pm->prepare(dev); + if (error) + return error; + } + return pci_dev_keep_suspended(to_pci_dev(dev)); }